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10-02-2012, 06:47 AM   #181
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Crippled mount (source:

MX from ouside (source:

MX from inside (right->left, source:

Der Mitnehmer für den Blendensimulator dreht ein ringförmiges Potentiometer, dessen Widerstandswert dem Belichtungsmesser die eingestellte Blende vorgibt.
The actuator for the aperture simulator rotates an annular potentiometer. Its resistance value determines the preset aperture, which is used by the exposure meter.

PS: The German nickname Blesator originates from Blendensimulator (aperture simulator).

112 #-163 iDon (I would definitely buy a de-crippled Pentax DSLR)
113 #-167 Pioneer (I would like to have the K-Mount on my dslr to work the way it does on my PZ-1p. That should not be that difficult to do.)
114 #like Nass (liked #---1)
115 #Bdfn HKMKonz
116 #Bdfn Hasenvater
117 #-170 Roob-N-Boots (Count me in.)
118 #-171 Davidw0815 (Open aperture metering with old lenses would be fantastic!)
119 #Bdfn Eisbär
120 #-179 MysteryOnion (De-cripple it!)

10-02-2012, 08:30 AM   #182
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QuoteOriginally posted by Davidw0815 Quote
Well, the problem is, that the middle of the split screen darkens in low light situation which then interferes with the metering. With normal daylight it's not much of problem until f/4. But if you stop down further, the split screen darkens and the metering is off. If I meter for example at f/1.4 and calculate the correct exposure for f/8 everything is fine.
Furthermore, metering is no problem with my lenses with A-contacts. Even if the split screen still interferes with metering, you just need to adjust the exposure compensation. With stop-down metering exposure compensation needs to be adjusted for every aperture setting differently. So I'm pretty confident that a de-crippled K-mount will improve things.
Buy a EE-S focus screen (AKA S-Type over at, it's linear and works wonders with stop-down lenses...
10-02-2012, 01:05 PM   #183
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QuoteOriginally posted by Sankon Quote
if your manual lens is set to M not A ( which is an aperture switch, not focussing obviously ! ), the camera has no control over the aperture at all. Set it to whatever you want, it will stay there :-)
Yes of course, but what if your manual lens doesn't have an AUTO/MANUAL aperture switch, for example an M or K series lens.
10-02-2012, 02:25 PM - 1 Like   #184
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Still use my K10 and Kx but the adaptall manual lenses now go on my Nikon D300 with the aperture connection, a Major improvement .
Just not acceptable that Pentax has not included this on the K5s after all they advertise the compatibility with the older lenses.
If Nikon can do it Pentax should.

10-02-2012, 06:22 PM   #185
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I don't get all this fuss over decrippling the mount. Pentax has provided two simple alternatives. First the Green Button which works perfectly fine. Second there is DoF Preview which gives you live metering with any lens. Change the aperture ring while using DoF Preview and the metering values change.

I have several M and K lens which I use very much. Once I got used to how each lens handles with any of the bodies I have owned the latest the K-5 I have not been impeded in any way using these lenses.

If it is such a problem for people using K and M lenses then find the equivalent A series lenses. As great as the M 50 f1.4 might be get the A 50 f1.4 as it is far superior as you have full aperture control. As great as people might think the K28 f3.5 is it is not better than the A28 f2.8 when the A28 is stopped down to f3.5.

I think Pentax has already supplied enough in their DSLR's for exactly what one needs to use any lens they have ever produced.
10-02-2012, 11:25 PM   #186
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...except for P-TTL support, which, strangely, is the only thing that could be made to work easily with the current crippled mount...

I've been asking this for 3-4 years now : please Pentax, when using non-A lenses, move the metering flash after the stop-down step, so the metering takes place at the selected aperture and flash power can be determined...
We know it works, you can trick the camera with some alu foil to make it work with m42, so if some redneck photo geek can think of that surely the Pentax engineers can do better?
10-03-2012, 12:28 AM   #187
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you can count me in. Pentax didn't cripple the mount with the 645D - you can still use the aperture ring with lenses that still have them - though the newer DA lenses are doing away with that.
10-03-2012, 02:19 AM   #188
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Please add my name to the list. I'd love a de-crippled K-mount and yes, it's a feature I would be prepared to pay for.

10-03-2012, 03:01 AM   #189
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QuoteOriginally posted by Rico Quote
I don't get all this fuss over decrippling the mount. Pentax has provided two simple alternatives. First the Green Button which works perfectly fine. Second there is DoF Preview which gives you live metering with any lens. Change the aperture ring while using DoF Preview and the metering values change.
indeed, alternatives are provided, but the metering is damn not accurate at all with this. when i use some K mount lens, the stop down metering always give around +3/4 EV more than it really need.
10-03-2012, 05:31 AM   #190
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The crippling is not an effective measure at preventing people from buying old lenses anymore. People are buying new glass because it has AF. So let me use my aperture rings the way they were meant to be used, please.
10-03-2012, 09:55 AM   #191
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10-03-2012, 06:27 PM   #192
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+1, count me in.
10-03-2012, 06:40 PM   #193
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+1. Seems like a good idea. It would mean that I could decripple my Tammy 90 f2.5 and pull out the plastic plug I inserted so the lens will act in stop down mode.
10-03-2012, 11:25 PM   #194
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+1. Decripple the K-mount!
10-04-2012, 12:17 AM   #195
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De-cripple it -Now!!

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